1. Field of the Invention
The present invention relates to a mechanism usable for controlling an uplink transmission power for a transmission from a communication network element, such as a user equipment or UE, to a communication network control element, such as a base station or eNB. In particular, the present invention is related to an apparatus, method and computer program product providing a transmission power control scheme for transmissions via uplink shared and control channels considering rapid changes in parameters used for calculating a transmission power when adjusting the transmission power.
2. Related background Art
Prior art which is related to this technical field can e.g. be found by the technical specification 3GPP TS 36.213, for example according to version 9.3.0, or 3GPP TS 36.321, for example according to version 9.3.0.
The following meanings for the abbreviations used in this specification apply:
eNB:evolved Node BE-UTRAN:evolved Universal Terrestrial Radio Access NetworkLTE:Long Term EvolutionLTE-A:LTE AdvancedPL:Path LossPUCCH:Physical Uplink Control ChannelPUSCH:Physical Uplink Shared ChannelRAR:Random Access ResponseSRS:Sounding Reference SymbolTPC:Transmission Power ControlTx:TransmitterUE:User EquipmentUTRAN:Universal Terrestrial Radio Access Network
In the last years, an increasing extension of communication networks, e.g. of wire based communication networks, such as the Integrated Services Digital Network (ISDN), DSL, or wireless communication networks, such as the cdma2000 (code division multiple access) system, cellular 3rd generation (3G) communication networks like the Universal Mobile Telecommunications System (UMTS), enhanced communication networks based e.g. on LTE, cellular 2nd generation (2G) communication networks like the Global System for Mobile communications (GSM), the General Packet Radio System (GPRS), the Enhanced Data Rates for Global Evolutions (EDGE), or other wireless communication system, such as the Wireless Local Area Network (WLAN) or Worldwide Interoperability for Microwave Access (WiMAX), took place all over the world. Various organizations, such as the 3rd Generation Partnership Project (3GPP), Telecoms & Internet converged Services & Protocols for Advanced Networks (TISPAN), the International Telecommunication Union (ITU), 3rd Generation Partnership Project 2 (3GPP2), Internet Engineering Task Force (IETF), the IEEE (Institute of Electrical and Electronics Engineers), the WiMAX Forum and the like are working on standards for telecommunication network and access environments.
In communication networks, in particular wireless communication networks, the setting of transmission powers for signaling between the entities of the communication network is an important aspect. For this purpose, several power control algorithms and schemes are proposed and developed for the various communication network types which are commonly known to a person skilled in the art and are thus not discussed here for the sake of simplicity.
Basically, for communications from a communication network element, such as a UE, to a communication network control element, such as a base station or eNB, the communication network element may be configured to conduct an uplink transmission power control processing on the basis of power control algorithms for setting and adjusting a transmission power for transmissions by different channels, such as a shared channel or a control channel. The communication network control element, when receiving a signaling, can detect whether the transmission power from the UE is sufficient, and then send a transmission power control command in order to let the UE increase, decrease or maintain the present uplink transmission power.
However, there may be situations in which a transmission power used by the UE is not changed in accordance with a TPC command received from a base station or eNB even though the UE has properly received the TPC.